Method of operating a compression refrigeration system



P. SCHLUMBOHM Sept. r26, 1939.

METHOD 0F OPERATING A COMPRESSION REFRIGERATION SYSTEM Original FiledNov. 19, 1932 Patented Sept. 26, 1939 PATENT OFFICE METHOD OF OPERATINGA COMPRESSION REFRIGERATION SYSTEM Peter Schlumbohm, New-York, N. Y.

original application November 19, 1932, sei-iai No. 643,344. Divided andthis application February 23, 1938, Serial No. 192,167.

vember 25, 1931 I 2 Claims.

Following my invention, frozen cooling medium 10 is applied within thecondenser, so that the vapor of the compressed refrigerant may contactdirectly the surface of the frozen cooling medium. The great advantageof this step will be evident from the following calculation: Ifthe'frozen l5 cooling medium would be applied from thev outside of thecondenser wall, some fi've to ten cen- 'tigrades would be lost for theheat transfer through the condenser wall;l If water is the refrigerantand water ice is the cooling medium,

2 this means that in the case of my method the true vapor pressure ofwater ice,.4.5 mm. Hg, would represent the condenser pressure, whereasin the other case the condenser pressure might easily rise, to pressureslike 9 mm. Hg.

25 Assuming that the water-refrigerant is evaporating in the evaporatorat a pressure of 2.25 mm, Hg, the ratio of compression would-have to be1:4 if the known art was-applied and could be reduced to 1:2 if my newmethod is used.

30 Lowering the ratio of compression is of special importance if thecompressors, which are required to compress the refrigerant, are ofthetype of the centrifugal compressor or of the type of the jet compressor,and just these types 35 are applied with preference for handling thelarge volume of refrigerant vapors as to be handled per B. t. u. in thecase of such refrigerants like water.

'I'he invention is illustrated diagrammatically,

40 partly in section and 'partly in view, in the acdenser 3. VThesuction tube of the compressor- In Germany Nois designated 5 and thepressure tube (exhaust) is designated 4. 'Ihe condenser 3 is filled withthe frozen cooling medium I, which practically will be in most casesfrozen`water. The frozen cooling medium is e. g. placed on ajgrili 6 toal- 5 low the melted cooling medium and the condensed refrigerant todrip off and to be withdrawn from lthe bottom of the condenser by meansof a tube 1. Following my invention it is important to withdraw theseliquids quickly 10 and constantly from the condenser before they wouldbeA warmed up by the condenser walls and cause higher presures inthecondenser than the pressure of the frozen cooling medium, which in thecase of -water ice is 4.5 mm. Hg. Following my invention this lowpressure of 4.5 mm.. Hg is further protected against the higher pressureof the jet of a water jet pump I9 by providing a liquid column S in thesyphon trap 2l. This arrangement makes it possible to withdraw liquidsfrom-the 4.5 mm. Hg pressure domain of the condenser into the about 12mm. Hg pressure domain of the water jet pumps suction chamber.

Following my invention, the low pressure in the condenser 3 isfurthermore maintained by providing an air pump 2| to withdrawnon-condensable gas like air through tube 9 from the condenser. Theexhaust tube I0 of the air pump maybe connected to the suction chamberof the water jet pump I8, as illustrated, the latter one working aspre-vacuum pump for the pump 2|.

Having now described the nature of my new method and having given anexample ofthe manner in which it may be performed, what I claim is:

1. 'I'he method of operating a compression refrigeration system in whichrefrigerant vapor is compressed and condensed in a. condenser in heatexchange with a cooling medium, comprising the 40 step of condensingthecompressed refrigerant vapor in direct contact with frozen coolingmedium and absorbing the condensation heat of the refrigerant by themelting of the cooling medium.

2..'I'he method as claimed in claimv 1, com- 45 prising the additionalstep of constantly withdrawing from the condenser liquid refrigeran

